Pivot pin work holder for sewing machines



Sept. 4, 1956 A. GUIDE 2,761,409

PIVOT PIN WORK HOLDER FOR SEWING MACHINES Filed Aug. 8, 1955 5. j 45 INVENTOR Anjbony Guide ATTORNEYS United States Patent 2,761,400 PIVOT PIN WORK HOLDER FOR SEWING MACHINES Anthony Guide, Raritan, N. J.

Application August 8, 1955, Serial No. 526,842

4 Claims. (Cl. 1122) This invention relates to attachments for spiral or circular stitch sewing machines, and more particularly to a novel movable pivot pin work holder by means of which the radius of stitching of a piece of material pierced by said pivot pin may be controlled while the work or material being sewn is securely held by said pin.

The present pivot pin work holder has been found to be particularly advantageous in combination with spiral stitching attachments used in the production of spiral stitching on a brassiere cup, but it is to be understood that the invention may be employed with other attachments for producing many different articles. It is clearly within the scope of the invention to provide a pivot pin work holder for pivotally holding any type of workpiece for circular, spiral, or other forms of stitching requiring pivotal movement of the workpiece.

In spiral stitching attachments of one type for which the improved work-holder is adapted, means are provided to be fixed to the sewing machine head and to be moved by a cam-driven mechanism operating in timed relation to the drive means for the stitching mechanism.

Such a device is described in my co-pending application Serial No. 463,354, filed October 20, 1954. The spiral stitching attachment as disclosed'therein includes a cam having a spiral periphery driven at a very low speed relative to the speed of the stitching mechanism, and a cam follower actuated by the spiral cam to move continuously in one direction during the stitching operation and at such a changing rate that the convolutions of the spiral seam are substantially equally spaced. The cam follower is connected with a movable work supporting member having a straight pivot pin engageable with the Work to continuously move the work laterally of the normal direction of stitching while the conventional work feeding means of the sewing machine causes the work to pivot about the pivot pin to thereby produce a spiral seam. In the devices heretofore employed, it has been necessary that the pivot pin cooperate with some additional or auxiliary means on the machine or attachment in order to hold the work on the pivot pin to prevent accidental disengagement of the work from the pivot pin during the lateral movement of the work while being stitched.

The present invention provides a pivot pin of such configuration as to eliminate the necessity for any auxiliary means to cooperate therewith for holding the Work. The improved attachment is not only simpler but also enables the capacity of the machine to be greatly increased by reducing the timerequired to position work on and remove work from the attachment.

The principal object of the invention is to provide a work-holder for an attachment for a sewing machine which will permit free pivotal movement of the work dur-' ing stitching while automatically preventing accidental disengagement of the work from the holder.

Another object is to provide a practical work holder for sewing machines which is of extremely simple design 2,761,400 Patented Sept. 4, 1956 "ice and construction and which is economical to manufacture and easy to use.

Another object is to provide a pivot pin type of work holder attachment which will speed up stitching operations by permitting the work to be mounted upon and removed from the attachment more rapidly than was theretofore possible.

Another object is to provide a work holder for spiral and/ or circular stitching machines which eliminates the necessity for any auxiliary means for retaining the work on the holder.

A further object is to provide a novel pivot pin type of work attachment which can be readily substituted for work holder attachments in present spiral stitch sewing machines, of the type shown, for example, in my prior Patents 2,674,693 and 2,674,964, and in my application,

supra.

Still further objects and advantages of the invention will become apparent from the ensuing description taken in conjunction with the accompanying drawings, where- Fig. 1 is a fragmentary front elevational View, partly in section, of a sewing machine head and spiral stitching attachment provided with the pivot pin work holder of the present invention;

Fig. 2 is a fragmentary plan view, partly in section, of the apparatus shown in Fig. 1;

Fig. 3 is an enlarged fragmentary sectional view taken on the line 33 of Fig. 2;

Fig. 4 is a perspective view of the present pivot pin work holder and its associated mounting plate; and

Fig. 5 is a plan view of a brassiere cup having a spiral stitch as produced by the present invention.

The pivot pin work holder and support of the present invention comprises a plate or base member carrying at one end a pin having an upstanding stem portion perpendicular thereto and an upright point portion offset from the stem portion by a sinuously bent upwardly inclined portion providing a laterally extending midportion adapted to hold work material against accidentally slipping off the pin.

Referring first to Figs. 1 and 2, there is shown a conventional sewing machine head 2 having the usual reciprocating needle 4, presser foot 6, and material-feeding means 8, arranged to feed material below the presser foot and needle in a direction normal to the plane of Fig. 1. The sewing machine head 2 includes a base 10 mounted on a table 11 by bolts or screws 12. A guideway 13 of generally channel shape is mounted on the table 11 by screws 14 and extends in a direction generally aligned with the longitudinal axis of the sewing machine head 2 and at right angles to the direction in which the work is moved by the feed means 8. The upper surface 15 of the web portion of the guideway 13 is substantially flush with the upper surface of the base 10 and is engaged by a work-control slide member 16 positioned within the guide channel. Suitable angle members 18 are secured by screws 19 to the guideway 13 and have flanges overlying the edges of the slide 16 to retain the slide in the guide channel. The slide 16 is further provided with a block 20 fixed on its upper surface and which carries an extending rod 22 to which is attached an upright arm 24. The arm 24 is adjustably secured within a tube 26 having a head 28 which, in turn, is fixed to a horizontal actuating rod 30 slidably carried within a guide member 32 mounted within a bracket 34 carried by the head 2. The actuating rod 30 is driven by a suitable cam mechanism (not shown) so as to move the slide 16 in a manner effecting the desired motion of the work during the stitching operation. That is to say, the rod 30 moves the slide 16 in a direction away from the needle 4 at a decreasing rate in order to produce uniform spacing of the convolutions of the spiral seam. Suitable cam mechanism for actuating the rod 30 is shown in my aforementioned application, Serial No. 463,354.

The slide 16 is connected with a Work holder and support member comprising a thin metal plate 35 extending over the upper surface 15 of the web of guideway 14 and above the upper surface of the base to a position closely adjacent the needle 4 and presser foot 6 when the slide is in its extreme right position. Figs. 1 and 2 show the slide 16 in a position it assumes after stitching has started and while said slide is being moved toward the left. The plate 35 has a smooth fiat top, bottom and sides and, as shown in detail in Fig. 4, is provided at its tail portion with threaded openings 36 for accommodating; screws 38, whereby it may be detachably affixed within a slot 16 provided in the lower surface of the slide 16. The forward end of the plate 35 is tapered as shown at 39 and its edges are slightly beveled or rounded od to provide smooth operation and avoid snagging the work material while it is being rotated and stitched. Near the extremity or tip of the plate 35 there is an upstanding, hardened steel pivot pin 40 fixed at one end of its stern portion 42 to the plate 35 and terminating at its other end in a sharp point 44. The stem portion 42 is relatively short and extends substantially vertically or perpendicularly from the plate 35 for a distance approximating the maximum thickness of the laminated material to be stitched. A typical workpiece is illustrated in Figs. 1 and 2 in the form of a brassiere cup 48. The pin 40 is bent on a curve at the upper extremity of its stem portion 42 and merges into a laterally upwardly inclined midportion 51, and is then reversely curved to form an upstanding point portion 50, which is substantially parallel to the stem portion 42. It will be noted that the pivot pin 40 is smoothly bent in a generally sinuous manner between the stem portion 42 and the point portion 50, and that the midportion 51 extends in a direction away from the needle 4, thereby facilitating the mounting of the cup centrally on the pin and its removal therefrom. The pin 40 may, if desired, be of substantially uniformly decreasing diameter from its stem end to its point to further accomplish this purpose.

In operation, when the slide 16 is at the leftvhand end of its stroke, a cup 48 to be sewn is manually placed in position by centering it upon the pivot pin 49, piercing the material by means of the point 44 and sliding it down along the pin until it is seated on the plate 35 and pivotally mounted on the stem portion 42. The laterally extending midportion 51 then lies generally parallel with the inner surface of the cup and holds the cup on the plate 35. The actuating cam (not shown) is retracted, thereby permitting the slide 16 and rod 30 to be manually moved toward the right to a position in which the cup can be slipped under the presser foot 6 and the pin 40 positioned in close proximity to the needle 4. The slide 16 is now in its fully advanced position. The stitching mechanism and lateral motion mechanism are now started and the workpiece 48 is automatically pivoted around the stem portion 42 of the pivot' pin 40 by the work-feed mechanism 8 throughout the stitching operation. The sinuously curved and laterally extending midportion 51 permits the work-piece 48 to freely pivot without any restriction and to flex so that the portion being stitched lies fiat relative to the base 10, while at the same time it prevents the cup from accidentally slipping off the pin. The rod 30 is moved toward the left by the actuating cam (not shown) at the appropriate speed to produce uniformly spaced spiral convolutions of stitches 54. At the end of the stitching operation, the presser foot 6 is raised and the workpiece 48 quickly slipped ofi the pivot pin 4%). Fig. 5 shows the cup as it appears at the end of the stitching operation. Successive brassiere cups 43 can be sewn by repeating the operations aforedescribed. It will be seen that the novel work holder and support thus provide a simple but effective means for pivotally holding and moving a workpiece during a spiral stitching operation.

While the invention has been described in combination with a spiral stitching attachment, it will be understood that such description is merely illustrative and not limiting. The invention may be used with other attachments for sewing true circles, instead of a spiral, and may be modified in its structure and mounting without departing from the principles thereof or from the scope or the appended claims.

I claim:

l. A work-piece holder for use with a sewing machine, comprising: a member; and a pivot pin, said pivot pin including a stem portion having one end thereof fixed in upright relation on said member, an upstanding point portion olfset from said stem portion, and a laterally extending midportion between said stem and point portions.

2. A work-piece holder as defined in claim 1, in which the member is elongated and the pin is mounted at one end thereof and wherein said member is flat and its side edges taper toward the end carrying said pivot pin.

3. Work-piece supporting and moving means adapted to be associated with a needle and work-feeding mechanism of a sewing machine to control the radius of stitching on a work-piece comprising: a guide adapted to be positioned at right angles to the direction of feed of said work-feeding mechanism; a slidable member mounted in said guide for movement in timed relation to said worlofeeding mechanism; and a work-piercing pivot pin carried by said slidable member, said pivot pin having an upstanding base portion and a sinuously bent portion extend-ing from said base portion and terminating in an upstanding point portion offset from said base portion, said sinuously bent portion including a laterally extending midportion, whereby, material pierced by said point portion may be slipped smoothly down onto said base portion and pivoted therearound during stitching while being held against movement off said base portion of said pivot pin by said laterally extending midportion.

4. In a sewing machine having stitch-forming means, means for feeding material past said stitch-forming means in a predetermined direction, drive means for said stitchforming and material-feeding means, and actuating means connected to said drive means movable in a direction transverse to said predetermined direction and away from said stitch-forming means: a work-supporting member connected to said actuating means to be actuated thereby, and a work-piercing pivot pin mounted on said work-supporting member adjacent said stitch forming means, said pivot pin having a generally upright stem portion, an upstanding point portion offset from said stem portion, and a laterally extending work hold-down midportion between said stem and point portions.

References Cited in the file of this patent UNITED STATES PATENTS 67,545 Hodgins Aug. 6, 1867 272,993 Vieman Feb. 27, 1883 287,044 Moore Oct. 23, 1883 341,148 Kempshall May 4, 1886 2,551,261 I Gensheimer May 1, 1951 

